The Superficial Cervical Plexus Block for Postoperative Pain Therapy in Carotid Artery Surgery. A Prospective Randomised Controlled Trial

Regional Anesthesia Techniques in Modern Neuroanesthesia Practice: A Narrative Review of the Clinical Evidence

Neurosurgical procedures are often associated with significant postoperative pain that is both underrecognized and undertreated. Given the potentially undesirable side effects associated with general anesthesia and with various pharmacological analgesic regimens, regional anesthetic techniques have gained in popularity as alternatives for providing both anesthesia and analgesia for the neurosurgical patient. The aim of this narrative review is to present an overview of the regional techniques that have been incorporated and continue to be incorporated into modern neuroanesthesia practice, presenting in a comprehensive way the evidence, where available, in support of such practice for the neurosurgical patient.

Regional Anesthesia for Vascular Surgery and Pain Management

Patients undergoing vascular surgery tend to have significant systemic comorbidities. Vascular surgery itself is also associated with greater cardiac morbidity and overall mortality than other types of noncardiac surgery. Regional anesthesia is amenable as the primary anesthetic technique for vascular surgery or as an adjunct to general anesthesia. When used as the primary anesthetic, regional anesthesia techniques avoid complications associated with general anesthesia in this challenging patient population. In this article, the authors describe regional anesthetic techniques for carotid endarterectomy, arteriovenous fistula creation, lower extremity bypass surgery, and amputation.

Effect of Bilateral Superficial Cervical Plexus Block on Postoperative Analgesic Consumption in Patients Undergoing Thyroid Surgery

Purpose

Patients complain of moderate-intensity pain following thyroid surgery. Superficial cervical plexus block (SCPB) can be employed as a component of multimodal analgesia after thyroid surgery. This double-blind, randomized study aimed to compare the effects of bilateral SCPB (BSCPB) on postoperative analgesic requirements following thyroid surgery.

Methods

A total of 60 American Society of Anesthesiologists (ASA) I-II patients who underwent elective total thyroidectomy under general anesthesia were randomly assigned to Group 1 and Group 2. After inducing general anesthesia, BSCPB was not administered to Group 1, whereas BSCPB was administered using a three-point injection technique with 0.5% levobupivacaine in Group 2. Patient-controlled analgesia (PCA) was applied by using tramadol in both groups for postoperative analgesia. Tenoxicam was administered as rescue analgesic to patients in case of numeric rating scale (NRS) >4. The postoperative consumption of tramadol, rescue analgesic requirement, and hoarseness, hematoma, signs of local anesthetic toxicity were recorded.

Results

The consumption of tramadol for PCA at two, six, 12, and 24 hours postoperatively, NRS scores in the recovery room, and the number of patients who used tenoxicam as rescue analgesic were significantly lower in Group 2 than in Group 1. The hemodynamic values were similar between the groups.

Conclusions

Our study demonstrates that BSCPB, when applied as a component of multimodal analgesia, is an effective method for reducing the analgesic requirements following thyroid surgery.

Pain management in patients with vascular disease

Vascular disease covers a wide range of conditions, including arterial, venous, and lymphatic disorders, with many of these being more common in the elderly. As the population ages, the incidence of vascular disease will increase, with a consequent increase in the requirement to manage both acute and chronic pain in this patient population. Pain management can be complex, as there are often multiple co-morbidities to be considered. An understanding of the underlying pain mechanisms is helpful in the logical direction of treatment, particularly in chronic pain states, such as phantom limb pain or complex regional pain syndrome. Acute pain management for vascular surgery presents a number of challenges, including coexisting anticoagulant medication, that may preclude the use of regional techniques. Within the limited evidence base, there is a suggestion that epidural analgesia provides better pain relief and reduced respiratory complications after major vascular surgery. For carotid endarterectomy, there is again some evidence supporting the use of local anaesthetic analgesia, either by infiltration or by superficial cervical plexus block. Chronic pain in vascular disease includes post-amputation pain, for which well-known risk factors include high pain levels before amputation and in the immediate postoperative period, emphasizing the importance of good pain control in the perioperative period. Complex regional pain syndrome is another challenging chronic pain syndrome with a wide variety of treatment options available, with the strongest evidence being for physical therapies. Further research is required to gain a better understanding of the underlying pathophysiological mechanisms in pain associated with vascular disease and the best analgesic approaches to manage it.

Ultrasound-guided bilateral superficial cervical plexus block is more effective than landmark technique for reducing pain from thyroidectomy

Purpose

Thyroidectomy causes postoperative pain and patient discomfort. Bilateral superficial cervical plexus block is a regional anesthesia technique that can provide analgesia during and after surgery. This study aims to compare the effectiveness of ultrasound (US)-guided versus landmark (LM) technique for bilateral superficial cervical plexus block in thyroidectomy.

Patients and methods

Thirty-six patients undergoing thyroidectomy were divided into two groups randomly (n=18); either US-guided (US group) or LM technique (LM group) for bilateral superficial cervical plexus block. Patient-controlled analgesia was used to control postoperative pain. Intraoperative opioid rescue, postoperative visual analog scale (VAS) score and opioid consumption were measured.

Results

The number of patients who required intraoperative opioid rescue was significantly lower in the US group (p≤0.05). There was no significant difference in postoperative VAS score at 3 hours (p>0.05), but postoperative VAS score at 6 and 24 hours was significantly lower in the US group (p≤0.05). Twenty-four hour postoperative opioid consumption was significantly lower in the US group (p≤0.05).

Conclusion

Ultrasound-guided bilateral superficial cervical plexus block is more effective in reducing pain both intra- and postoperatively compared with landmark technique in patients undergoing thyroidectomy.

Combined Carotid Endarterectomy and Retrograde Stenting of the Supra-Aortic Trunk: Does Cervical Block Offer Advantages?

BACKGROUND

Atherosclerosis of the carotid artery is a major source of stroke. In some cases, atherosclerosis occurs at several positions within the carotid artery. Carotid endarterectomy (CEA) in combination with retrograde balloon angioplasty and stenting of a brachiocephalic or common carotid artery stenosis has been described as efficacious and safe procedure to prevent stroke in these cases. The aim of this study was to analyze the impact of anesthetic techniques on hemodynamic factors, operation time, duration of clamping, and postoperative pain.

METHODS

A retrospective analysis of patients undergoing CEA in combination with retrograde stenting under either general anesthesia (GA) or cervical block (CB) was carried out. Preoperative risk factors were analyzed as well as operating and cross-clamping time, hemodynamic factors, perioperative complications, postoperative pain, application of pain killers, and duration of intensive care unit (ICU) and hospital stay.

RESULTS

Operating (GA: 193 ± 91 min vs. CB: 125 ± 52 min, P = 0.029) and cross-clamping time (GA: 34 ± 12 min vs. CB: 26 ± 9 min, P < 0.001) were shorter under CB. Patients under CB were hemodynamically more stable and required less norepinephrine (GA: 1.1 ± 0.6 mg vs. CB: 0.1 ± 0.1 mg, P < 0.001) and crystalloids (GA: 2,813 ± 1,173 mL vs. CB: 1,088 ± 472 mL, P < 0.001). Postoperative pain levels (GA: numeric rating scale 4.3/10 vs. 2.0/10; P = 0.004) and requirement of pain killers were also lower within the CB group.

CONCLUSIONS

Synchronous CEA and retrograde balloon angioplasty and stenting of a brachiocephalic or common carotid artery stenosis under CB is associated with reduction of operating and cross-clamping time, improved hemodynamical stability, lower postoperative pain, shorter ICU and hospital stay, and it offers the advantage of a continuous neurological monitoring.

Evaluation of the Analgesic Effect of Bilateral Superficial Cervical Plexus Block for Thyroid Surgery: A Comparison of Presurgical with Postsurgical Block

Bilateral superficial cervical plexus block may help in reduction of postthyroidectomy pain. The aim of this study was to evaluate the influence of bilateral superficial cervical plexus block (BSCB) given either presurgically or postsurgically on analgesia in postthyroidectomy patients. Sixty adult euthyroid patients were randomly allocated to one of the three groups, to receive BSCB either presurgically (group A) or postsurgically (group B). Both of the above groups were compared with parenteral analgesics (group C). Thyroid surgery was performed according to a standardised procedure. Postoperative pain was assessed by visual analog scale (VAS), with 10 being the worst pain and 0 being no pain, when patient was fully awake and extubated (0) and after 1, 2, 4, 8, 12, 18, 24, 36 and 48 h. VAS was assessed at four phases: at rest, neck movements, vocalisation and swallowing. Total use of intraoperative fentanyl was noted. The time for first rescue analgesic was also noted. There was no significant statistical difference amongst three groups as regards demographic data and duration of surgery. Patients given BSCBs (either presurgically or postsurgically) had significant lower VAS at all four phases of pain assessment as compared to group C. The time for first rescue analgesia was the earliest in group C. We concluded that BSCB whether given presurgically or postsurgically significantly reduce pain intensity and opioids requirement in postoperative period after thyroid surgery.

Local anaesthetic infiltration at the end of carotid endarterectomy improves post-operative analgesia

BACKGROUND

Wound infiltration at the end of carotid endarterectomy under general anaesthesia is a simple technique that can be delegated to the surgeon. It was hypothesised that this technique could improve early post-operative analgesia by reducing the need for post-operative opioids.

METHODS

Forty patients underwent carotid endarterectomy under general anaesthesia with desflurane and remifentanil supplemented with morphine for post-operative analgesia. In a prospective double-blinded randomised study, patients were allocated pre-operatively to receive either subcutaneous infiltration of both wound edges with 20 ml of 0.75% ropivacaine or infiltration with isotonic saline. The primary outcome was morphine consumption while in the post-anaesthesia care unit (PACU). Pain scores at rest and movement, sedation, and patient satisfaction were the other main outcomes used to assess post-operative analgesia.

RESULTS

The median dose of morphine administered in the PACU was 2 mg [0-3] in the ropivacaine vs. 4 mg [3-6] in the placebo group (P = 0.0004, Mann-Whitney's test). Pain at rest and at movement was lower in the ropivacaine group throughout observation in the PACU. No difference was found for both pain and opioid consumption after discharge from the PACU or for patient satisfaction. Sedative events in the early post-operative period were less frequent in the ropivacaine group.

CONCLUSIONS

Local anaesthetic wound infiltration performed before closure reduces the need for additional opioids, lowers the immediate post-operative pain and improves alertness. These results argue for the use of local infiltration anaesthesia for carotid endarterectomy.

Regional anesthesia for vascular surgery

Patients presenting for vascular surgery present a challenge to anesthesiologists because of their severe systemic comorbidities. Regional anesthesia has been used as a primary anesthetic technique for many vascular procedures to avoid the cardiovascular and pulmonary perturbations associated with general anesthesia. In this article the use of regional anesthesia for carotid endarterectomy, open and endovascular abdominal aortic aneurysm repair, infrainguinal arterial bypass, lower extremity amputation, and arteriovenous fistula formation is described. A focus is placed on reviewing the literature comparing anesthetic techniques, with brief descriptions of the techniques themselves.

Regional anaesthesia techniques for carotid surgery: the state of art

PURPOSE

This review will analyse some aspects of regional anaesthesia (RA) for carotid endarterectomy (CEA), a surgical procedure which requires a strict monitoring of patient's status. RA remains an important tool for the anaesthesiologist. Some debates remain about type and definition of regional anaesthesia, efficacy and safety of the different cervical block techniques, the right dose, concentration and volume of local anaesthetic, the use of adjuvants, the new perspectives: ultrasonography, the future directions.

METHODS

A literature search was performed for journal articles in English language in the PubMed Embase and in The Cochrane Library database, from January 2000 to December 2013. The electronic search strategy contained the following medical subject headings and free text terms: local anaesthesia versus general anaesthesia for endarterectomy, superficial and deep cervical block, complications of cervical nerve block, ultrasound guidance of superficial and deep cervical plexus block.

CONCLUSIONS

The gold standard for RA will be achieved after overcoming a number of limitations by a more extensive use of ultrasonography, by combining general and regional anaesthesia, including conscious anaesthesia, by defining the appropriate volume, concentration and dosage of local agents and by addition of adjuvants.

Unexplained fever after bilateral superficial cervical block in children undergoing cochlear implantation: an observational study

PURPOSE

In an effort to decrease postoperative opioid requirements, intraoperative bilateral superficial cervical plexus block (BSCPB) was recently adopted for all our children undergoing general anesthesia for bilateral simultaneous cochlear implantation (BSiCI). Several cases of early postoperative fever were noted after the adoption of BSCPB. Our aim was to determine if an association exists between BSCPB and early postoperative fever in children undergoing BSiCI. As a secondary outcome, we studied the efficacy of BSCPB in altering postoperative analgesic requirements.

METHODS

We conducted a retrospective cohort study of 91 consecutive children who underwent BSiCI. The series included 34 patients who received BSCPB (Block Group) and 57 patients who did not receive BSCPB (No-block Group).

RESULTS

The median age (range) was 15.4 months (eight months - 15 yr). A significant association was found between BSCPB and postoperative fever (P = 0.006). Eighteen (19.7%) children developed fever in the first 24 hr after surgery (Block Group: 12/34 [35%]; No-block Group: 6/57 [11%]; P = 0.006). The Block Group was 4.8 times more likely to develop early postoperative fever after adjusting for other variables (P = 0.004). The Block Group spent more days in hospital after surgery compared with the No-block Group (P = 0.043). Other vital signs showed no major deviation from the normal ranges, and daily physical examinations revealed no obvious source of infection in children who developed postoperative fever.

CONCLUSION

Bilateral superficial cervical plexus block may increase the risk of postoperative fever in children undergoing BSiCI. In this series, BSCPB was associated with a longer hospital admission. The etiology of the fever is undetermined, although it can be hypothesized that BSCPB resulted in unintended block of the phrenic nerves leading to diaphragmatic paralysis, atelectasis, and early postoperative fever in young children.

Use of invasive placebos in research on local anaesthetic interventions

Placebos play a vital role in clinical research, but their invasive use in the context of local anaesthetic blocks is controversial. We assessed whether recently published randomised controlled trials of local anaesthetic blocks risked harming control group patients in contravention of the Declaration of Helsinki. We developed the 'SHAM' (Serious Harm and Morbidity) scale to assess risk: grade 0 = no risk (no intervention); grade 1 = minimal risk (for example, skin allergy to dressing); grade 2 = minor risk (for example, subcutaneous haematoma, infection); grade 3 = moderate risk (with or without placebo injection) (for example, neuropraxia); and grade 4 = major risk (such as blindness, pneumothorax, or liver laceration). Placebo interventions of the 59 included trials were given a SHAM grade. Nine hundred and nineteen patients in 31 studies, including six studies with 183 children, received an invasive placebo assessed as SHAM grade ≥ 3. A high level of agreement (78%, κ = 0.80, p < 0.001) for SHAM grades 0-4 increased to 100% following discussion between assessors. More than half of the randomised controlled study designs subjected patients in control groups to risks of serious or irreversible harm. A debate on whether it is justifiable to expose control group patients to risks of serious harm is overdue.

Thyroid surgery under monitored anesthesia care (MAC)

BACKGROUND

Thyroid surgery is usually performed under general anesthesia, but thyroid surgery under monitored anesthesia care (MAC) has become re-introduced. We report our experiences of 40 cases of thyroid surgery under MAC.

METHODS

Forty patients were enrolled in this study. Bilateral superficial cervical plexus block (BSCPB) was performed by using 1% mepivacaine with 1 : 200,000 epinephrine. After BSCPB, patients were sedated with propofol and fentanyl. Postoperative pain, sore throat, hoarseness, and postoperative nausea and vomiting (PONV) were assessed.

RESULTS

Mean postoperative pain VAS were 1.3, 1.2, 1.0, 0.8 and postoperative sore throat VAS 1.4, 1.4, 1.1, 0.9 at PACU (post-anesthesia care unit) and postoperative 3, 6, 12 h, respectively. The incidence of hoarseness was 25, 5, 2.5%, and 0% and PONV were 0, 5, 10%, and 7.5% at PACU and postoperative 3, 6, 12 h, respectively.

CONCLUSIONS

Thyroid surgery under MAC may be a suitable alternative to general anesthesia.